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engine not hitting on all

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Old Feb 10, 2013 | 02:29 PM
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Default engine not hitting on all

I got my 1968 in oct,12 and has had a miss when I got it. I have changed plugs twice replaced wires ,dist cap & rotor. Still there.I went to Pertronix lobe sensor ele ign.Still there.called edelbrock and put on an 2101 intake and 1406 carb.Still there.Compression test has all over 100.Did a leakdown test and is good.Adjusted valves.Still there. Can take 3 plug wires off and no difference in running.One on one side and 2 off other side.Where to go??? I have swaped out the good one with where the bad is and still the same ones not hitting. Swaped the plugs then the wires one at a time. The same cylinders not hitting but getting fire. ??????
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Old Feb 10, 2013 | 02:38 PM
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do you have your old distributor still ? What if you swap that in with the good plugs and wires and carb? Does it Pop and backfire?

I just went through this myself and it is very frustrating. I sorted it out but wife said she thought I was gonna have a meltdown. I had both fuel and ignition issues. Once I sorted the ignition out, I used an A/F gauge to tune the carb.

This may be a good excuse to pick up a wideband if you were wanting one anyway.

Last edited by johnt365; Feb 10, 2013 at 02:47 PM.
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Old Feb 10, 2013 | 02:41 PM
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From: anchorage ak
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That's odd. What was the compression on those three cylinders? It takes fuel/air, spark to fire. If you put a plug in those three spark plug wires and ground the plug do each one at a time to see If there firering. What do the plugs look like on those three cylinders versus the other cylinders? What kind of vacuum is it pulling and is the gauge steady or does the needle move?
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Old Feb 10, 2013 | 03:22 PM
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Yes I still have the old tach drive dist.Compression good on cylinders not hitting. I am retired old school and some of this is new to me.I have never pulled vaccum check?? I put a plug that I replaced with on plug wire and layed it on frame and started it so i know it is getting fire.I also am having a meltdown over this, never had such a hard time over something most likely simple.

Last edited by nightynine; Feb 10, 2013 at 03:31 PM.
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Old Feb 10, 2013 | 04:23 PM
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Are the valves opening ?
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Old Feb 10, 2013 | 05:43 PM
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From: anchorage ak
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Calm down. Youll get this. What was the compression on each cylinder? For vaccum youll need a vaccum guage, sells for 30 to 40 dollars at schucks. What do the plugs look like in the cylinders that are missing. Do you have the firering order right? As die hard is asking, do the valves open, you can checkthis by removing a valve cover and watching the rocker arm open and close the valve. I find that when something like this is happening its a good thing to write down everything you check and the results.
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Old Feb 11, 2013 | 07:50 AM
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Default bluedawg

Originally Posted by bluedawg
Calm down. Youll get this. What was the compression on each cylinder? For vaccum youll need a vaccum guage, sells for 30 to 40 dollars at schucks. What do the plugs look like in the cylinders that are missing. Do you have the firering order right? As die hard is asking, do the valves open, you can checkthis by removing a valve cover and watching the rocker arm open and close the valve. I find that when something like this is happening its a good thing to write down everything you check and the results.
The compression is between 105 to 120 on the 4 I checked{2 bad cylinders and two good firing ones}I will get a vaccum gauge also and did fireing order a couple times and beleive it is right. The valves are opening I guess as they are moving when I adjusted on them .I have a guy coming over this morning that is also old school to take a look. I most likely haven't done something right ? But maybe thats the guy sold it to me.I'm not giving up till I get it and thanks for the continued help as I need it.Its been a long time sense I have been under the shade tree.The plugs look ok ? They are not oily or wet but a little darker color then the firing ones

Last edited by nightynine; Feb 11, 2013 at 07:53 AM.
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Old Feb 11, 2013 | 08:47 AM
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I googled your dist , it appears like a good one however some have had issues with its lobe sensor , and all else being equal it can only be distributor related , could even be a very weak coil , so go and check all dist connections and call the tech support for that distributor.
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Old Feb 11, 2013 | 11:35 AM
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Originally Posted by diehrd
I googled your dist , it appears like a good one however some have had issues with its lobe sensor , and all else being equal it can only be distributor related , could even be a very weak coil , so go and check all dist connections and call the tech support for that distributor.
I Got It Fixed, I am so tickeled!! It turned out to be the carb,We took it apart and had some jelly like stuff in it where it had been sitting. It was getting gas but not enough in the right places.Cleaned it out and put back together and it runs like a new car.Hope this can help someone with same issue. Thanks to all
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Old Feb 11, 2013 | 04:52 PM
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From: anchorage ak
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good deal. you fixed it with out taking it any were. thats always the best feeling.
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